Light bulb



FIG. 1 is a perspective view of the light bulb;

FIG. 2 is a side elevational view of the light bulb, the side elevational view from all sides of the light bulb being the same;

FIG. 3 is a top plan view of the light bulb; and,

FIG. 4 is a bottom plan view of the light bulb.

The broken line showing of bottom portion of the light bulb is included for the purpose of illustrating only and forms no part of the claimed design. 

The ornamental design for a light bulb, as shown and described. 